They claim to have been involved in talks for three years, with no signs of ASEATA, the Association of Airport Ground Support Services Companies, making any improvement.

USO Aéreo released a statement today warning of the strike action as they dispute salary.

”After almost three years of negotiations to agree the IV Collective Agreement of the Ground Support Services Sector, ASEATA employers have continued to show their immobile attitude to try to agree on fundamental aspects that have to do with the system of subrogation, salary and other remuneration variable economic concepts (sic),” said the statement.

Another source of frustration among the workers is some of their work being outsourced.

The unions said in a statement: "We cannot allow more companies to continue operating in our labour market with wild deals, using precarious contracts and workers' salaries."